Improvement in hydraulic feed for revolving rock-drills



' 2Sheets--Sheet1. R. ALLISON. Hydraulic Feed for Revolving Rock-Drills.

N0, 145,77? :0 Patented Dec.23,1873.

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2 Sheets--Sheet 2. R. ALLISU N.

Hydraulic Feed for Revolving Rock-Drills; No. 145,775. Patented Dec.23,1873.

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UNITED STATES PATENT OEEIoE.

ROBERT ALLISON, OF PORT CARBON, PENNSYLVANIA.

IMPROVEMENTIN HYDRAU LIC FEED FOR REVOLVING ROCK-DRILLS.

Specification forming part of Letters Patent No. 145,775, dated December23,1873; application filed December 10. 1873.

To all whom it may concern Be it known that I, ROBERT ALLISON, of PortCarbon, in the county of Schuylkill and State of Pennsylvania, haveinvented a new and useful Improvement in Hydraulic Feed for RevolvingRock-Drills; and I do hereby.

declare the following to be a full, clear, and exact descriptionthereof, which will enable others skilled in the art to which itappertains to make and use the said improvement, reference being had tothe accompanying drawing, which forms a part of this specification, andin which-- Figure 1, Sheet 1, is an elevation of my improvement; Fig. 2,Sheet 2, a section on the line a: m, Fig. 1; and Fig. 3, Sheet 2, asection on the line 3 y, Fig. 2.

The same parts are denoted by the same letters in all the figures.

This improvement relates to that class of rock-boring machines whichoperate by rota-.

tion and continued pressure, and I have represented it as applied to aLeschot or diamond drill. It consists in the combination of hydrauliccylinders with a revolving drill-spindle, carrying the drill-rod, andarranged externally to said cylinders, and so connected with theirpiston-rods as to be moved forward or back by pressure on the pistons.It also consists in the combination, with said cylinders and theirsupply and discharge pipes, of a fourway cock, by which the feed of thedrill is regulated or reversed, as hereinafter described.

T in the drawing represents the swivel head or plate, by which thedrilling apparatus is attached to the engine or driving power, and onwhich are cast the upper and lower concave ,rear bearing-plates a a ofthe hydraulic cylinders A A, sleevepinion H, and lower sleeve I. Tothese bearing-plates are bolted corresponding front concavebearing-plates al a}, shown i1 Fig. 1. The cylinders A A are held inplace by being turned down one-sixteenth of an inch bearing of therevolving hollow spindle E. This spindle is made with collars fittinginto box I), and carries the hollow drill rod V, which is secured to itby a chuck, F. U is the diamond bit, screwed into rod V. The spindle Eis revolved by a spline on the bevel sleeve-pinion H, which meshes withthe bevel driving-gear. This pinion has collars above and below thebearing -plates to keep it in place, as shown in Fig. 3. I is a lowersleeve, likewise splined to the spindle and kept in place by top andbottom collars. The bearings in which H and I revolve are lined withanti-friction metal. S is a guide for the crosshead, projecting from theswivel head and serving to steady the lower end of the spindle. To theupper ends of cylinders A A is attached the pipe 0 opening into bothcylinders. Their lower ends are similarly connected by the pipe N. K isa four-way cock opening into pipes N and O, hose J, (which leads fromthe pump or other source of water supply,) and wastepipe Q, so that,when pipe 0 is open to hose J, pipe N is open to Q, and vice versa. M isa'hose to carry water to the drill-rod, to the top of which it isattached by the usual swivel connection, the other end of M beingconnected with hose J through valve L, by which water is admitted to orshut off from the drill-rod. P is an adjustable spring safety-valve, andR a pressure-gage, both placed on pipe 0.

The operation of this improvement is as follows: The machine having beenset up in place, and the drill-rod and bit attached, the water from thesteam-pump or other source of supply is turned on, and the valve Lpartly opened,

permitting water to flow through the drill-rod to the bit. The enginewhich drives the bevelgear is now started, and the four-way cock Kopened, so as to admit Water to the pipe 0 and upper end of thehydraulic cylinders, thereby pressing thepistons and cross-headdownward, and forcing the bit against the rock with a pressure which isindicated by the gage R, and may be regulated by partially closing cockK or opening it wider. When the hole has been drilled as far as thepiston-stroke permits, the engine which drives the bevelgear is stopped,valve L closed, swivel connection of hose M detached, chuck F loosened,and the cock K is then reversed, connecting the pipe N-and lower ends ofthe cylinders with the water supply, and thereby forcing the pistons andspindle upward, the water above the pistons escaping through waste-pipeQ. Another section of dri1l-rod is then attached in the usual manner,and the operation proceeds, as before.

Before commencing work, it will be well to turn on the water both aboveand below the pistons, so as to run them up and down once or twice, tosee if the passages are all open and the machine in working order beforethe drillrod is attached.

The. adjustable safety-valve may be set so as to relieve the waterpressure whenever it exceeds a certain limit, and by this means thediamonds are protected from excessive pressure and consequent injury.

Should the bit become choked, it can be lifted from the bottom of thehole by reversing-cock K, and held in this position until the debris hasbeen washed out, without stopping the rotating machinery.

What I claim as my invention, and desire to secure by Letters Patent ofthe United States, 1s-

1. The combination, substantially as described, of the cylinders,pistons, and pistonrods with a spindle located outside of saidcylinders, which carries the drill-rod, and is connected to said piston-rods, so as to be advanced or withdrawn by hydraulic pressure 011the pistons.

2. The combination, with the cylinders A A and pipes O, N, J and Q, ofthe four-Way cock K, by which the feed of the drill is regulated orreversed, substantially as above described.

ROBT. ALLISON.

W'ituesses:

M. S. PHILLIPS, JOHN L. SHIssLER.

